Excavator for trenches, cuttings, or the like.



No. 703,972. I Patented July I,. I902.

E. SCHDFIELD.

EXCAVATDB FOB TRENCl-IES, CUTTINGS, OR THE LIKE.

Application filed Mar. 8, 1902.)

(No Model.) 2 Sheets-Sheet I.

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No. 703,972. v Patented July 1, 1902. E. SCHOFIELD;

EXCAVATOR FOB TBENOHES, GUTTINGS, OR THE LIKE. (Application filed Mar. 8, 1902. (No Model.) 2 Sheets-Sheet 2.

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UNITED STATES.

ATENT FFICE.

ERNEST SCHOFIELD, OF LEEDS, ENGLAND.

EXCAVATOR FOR TRENCHES, CUTTIN GS, OR THE LIKE.

SPECIFICATION forming part of Letters Patent No. 703,972, dated July 1, 1902. Application filed March 8,1902, Serial No. 97,311. (No model.)

No. 18,061, bearing date September 10,190 1 of which the following is a specification. The object of this invention is to provide means for rapidly, efficiently, and economically excavating and clearing trenches, cuttings, and the like, especially where the depth is very considerable compared with the width, and to enable the depth-and the inclination of the face to be adjusted with at inost a momentary stoppage of themachine.

The invention provides for trenches of different widths being excavated bythe machine and also for varying the character of the action of the tools on the working face of the trench. These objects I effect by ai'machine comprising a driving rod or rods carrying the excavating-tools, a thrust rod or rods attached'at their lower ends to the driving rod or rods, a pair of cranks or.crank-shafts, the upper part of the driving rod or rods and of the thrust rod or rods being attached by clamp and hinge connections to the cranks.

or the cranks of the two crank-shafts, re spectively, which latter arerotated in the same direction and at the same speeds by any suitable or convenient gearing, the whole being mounted on a platform on wheels carrying a bucket elevator to remove and raise the loosened materiahand provided with mechanism for traveling the'platform as the excavation proceeds. Such means are illustrated by the accompanying drawings, of which Figure 1 is a side elevation, and Fig. 2 a plan.

A indicates the platform on which the machine is carried, the platform itself being mounted on wheels B, running ona pair of rails or tram-lines laid one on each side of the trench to be excavated.

0 indicates the sideframes, to which are secured the engine D or other motor driving the machine.

E is the boiler. I

F is an inner foundation-plate provided with upstanding brackets G, to which the lowerends of the four inclined posts ll of the braced elevator-frame are abutted and secured.

a a are the driving-rods, to the front side of the lower half of which are secured the excavating-tools Z2, which in the drawings are shown as bent-spike cutters, 0 being narrow spades The form of the excavating-tools may be varied as deemed most suitable by the contractor. The extreme lower part of the rods a are preferably curved backward, so as to. bring the loosened material nearer to the lower end of the elevator, to be afterward referred to. The rods aare securedi n clampingpieces e, which are provided on the rear side with split sockets or journals d, fitting the crank-pins of the crank-shaft f. By slackening the bolts of the clampingpieces 6 the position of the rods acan be readilyadjusted to suit the depth of the trench to beexcavated. The crank-pins are made considerably longer than the length of the sockets or journals d, so that by moving the washers g to the one side or the other or using narrower washers on both sides of the the rods athat is, the width of the trench or cutting-can be varied.

i t' are the thrust-rods, which are connected at their lower ends to the lower part of the driving-rods o, a. The upper ends of these thrust-rods are connected to the crank-pins of a second crank-shaftj by clamping-pieces and split sockets or journals in exactly the same manner as described for the connection of the driving-rods a a to the crank-pins of the crank-shaft f.

The crank-shaftsfandj are rotated in the same direction and at the same speed and usually with both cranks in the same angular position. The motion of the points of the excavating-tools is in this case circular; but by altering the angularposition of the cranks with respect to each other within short limits the motion becomes elliptical, or if the cranks have unequal throws the motion is that of a distorted ellipse. Bysuch alterations, therefore, the action of the tools may be varied from that of a scraping action to a percussive action. By altering the position of the clamping-pieces e on the one pair of rods-say the thrust-rods-without correspondingly alterin g the position of the clamping-pieces on the other pair of rods-say the driving-rods-the inclination of the working face may be varied.

The crank-sh afts f and j are geared together by two large wheels is and Lof equal size, and to obtain the same direction of rotation an intermediate wheel on is interposed between the two. The wheel Z is driven by the pinion on the shaft 19 of the motor. In the plan the pinion o is shown slid sidewise on the shaftp out of gear with the wheel Z, in which case the rods a andt'are out of action.

The upper ends of the braced posts H carry the bearings for the top tumbler-shaft g, on one end of which is fitted the chain-wheel for the driving-chain r of the elevator.

sis the driving-shaft for the chain 7, the opposite end of the shaft 8 having a wheel 25 gearing with a wheel it, mounted on the far side of the crank-shaft)". The lower tumblershaft '0 is carried at the lower end of the Vertical beam to, the upper end of which slides in a box-guide formed by the plates x a: y y, to the former of which it can be bolted in any position required by the depth of the trench .to be excavated.

z z are the buckets, and 1 1 the links of the bucket-chain, the length of the chain being altered, if necessary, by the removal or addition of links and buckets to suit the depth of the trench to be excavated.

2 is a chute (not shown in plan) into which the excavated material is thrown by the bucl ets as they pass over the top tumbler and is thence discharged sidewise either onto the ground ready to be refilled into the trench or to be dumped into wagons for removal.

The provision for gradually advancing the excavator as the face of the trench is excavated consists of a worm-wheel 3 on the axle of the pair of rear wheels, a worm 4E, gearing with the same and fitted on the lower end of a vertical shaft 5, bevel-wheels 6 and 7, crossshaft 8, carrying a gear-wheel 9, gearing with a wheel 10 on the crank-shaft f. To move the platform A more rapidly, as may be required when the rods a and t are outof action, the gear-wheel 10 is slid, by means of the clutch 11, out of gear with the wheel 9, and the gear-wheel 12 on the shaft 19 of the motor is slid by its clutch into gear with the wheel 9.

It will be evident that in the case of narrow trenchwork one driving-rod a only may suffice, while in the case of very wide work more than two driving and two thrust rods may be employed; also, that the exact arrangement of gearing as described and shown is not essential. Thus, for example, the wheels and Z may be made as chain-wheels connected by a chain-drive instead of by the intermediate pinion m.

to the shaft 19 driving-rods a. a, carrying excavating-tools Z), and thrust-rods t' t connected together toward their lower ends and respectively to the cranks of the shafts f and j a bucket elevator comprising buckets 2 link chain 1 adjustable vertical beam 10 carrying the lower tumbler-shaft o top tumbler-shaft q driving-chain'r and driving-shaft sand platform-traversing mechanism com prisin gworm wheel 3 on the axle of one of the pair of wheels B worm 4 vertical shaft 5 bevel-wheels 6 and 7 cross-shaft 8 and connecting gear-wheels between the shafts s and 8 and the motorshaftp respectively all substantially as herein set forth.

2. In excavators of the type herein referred to the combination of a platform A mounted on wheels B a motor D motor-shaft 19 a pair of crank-shafts f andj geared together and to the motor-shaft p driving-rods a a carrying excavating-tools a b thrust-rods a; 2' connected at their lower ends to the driving-rods a a.

clamping and split journal-pieces e d a bucket elevator comprising buckets 2 link chain 1 adj nstable vertical beam w carrying the lower tumbler-shaft '0 top tumbler-shaft q drivingchain '7 and driving-shaft s and gear-wheels 6 and u all substantially as and for the purposes specified.

3. In excavators the combination of socalled driving-rods a carrying excavatingtools I) c, thrust-rods ti connected at their lower ends to the driving-rods a pair of crankshaftsf and j geared to rotate in the same direction and clamping and split journalpieces e (Z- all substantially'as and. for the purposes specified.

4. In excavators the combination of a travcling platform A carrying a motor D and frames C with a pair of crank-shafts f andj mounted thereon so-called driving-rods a a. carrying excavating-tools b c thrust-rods 11 2' connected at their lower ends to the rods 0. 0t platform-traversing mechanism comprising worm-wheel 3 worm 4 vertical shaft 5 bevelwheels 6 and 7 cross-shaft 8 and gear-wheels ERNEST SOHOFIELD.

'Witnesses:

J. CLARK JEFFERSON, W. LAURES Moss.

between the motor-shaft p and the crank- 

